In other words, the ratings were close to double compared to last season, and that’s remarkable.

It also had the most viewers of any broadcast show that aired last night, though Fox’s new Ryan Murphy series 9-1-1 and Modern Family both beat TAR in the 18 to 49 demographic.

I now generally avoid writing stories about overnight ratings because television viewership is so much more complicated than it used to be. Ratings are down across television for too many reasons to list here. While overnight ratings do include those who watch on a DVR on the same day, anyone who watches later aren’t reported for some time. And though ratings are still important, TV networks are increasingly considering other metrics when judging a show’s success.

The amazing Amazing Race increase is likely not attributable to any one factor, and ratings could change in either direction once the show moves to its 9 p.m. timeslot and airs some two-hour episodes.

But here are some things that I think probably had an effect:

Last season aired in the challenging Thursday at 10 p.m. timeslot.

This season the show is in Survivor’s timeslot, Wednesdays at 8, where CBS fans are used to seeing reality TV.

It’s airing in the gap between Survivor seasons, when CBS usually doesn’t have any reality TV.

There are famous-ish teams, whose collective fanbases might have helped bump up the ratings a bit. That includes Big Brother’s Cody and Jessica, who may have encouraged some Big Brother fans to watch a show they might not have otherwise watched.

The episode itself felt different to me, though I’m not quite sure why. The production values didn’t quite seem up to the usual level of super-high-quality that the show has been known for.

Perhaps it was the structure of the episode, which started with not much of a race to Iceland, and just kind of jumped around from thing to thing, but ended with a dramatic photo finish—literally two teams crossed the mat at the same time.

And on top of that, another team had just completed a 30-minute penalty and checked in; a few more seconds and they would have been eliminated because of the penalty.